In a recent Nature paper, quantum startup Alice & Bob demonstrated the control and protection of superconducting qubits “at an unprecedented level” by implementing a cat qubit approach.
This approach extends the quantum control of a cat qubit with bit flip times of milliseconds to tens of seconds – an improvement of four orders of magnitude over previous demonstrations. This achievement represents a crucial step in scaling this dynamic qubit platform toward fault-tolerant quantum computing.
The new protocol in the paper allows for the control of quantum states without the use of a transmon, a common circuit used by many quantum companies, but one of the major sources of bit-flip errors. This design also minimizes the footprint of the chip by removing drivelines, cables and instruments.
Alice & Bob’s Boson 4 chip, recently added to Google Cloud, now reaches over 7 minutes of bit-flip lifetime, so the results in Nature can be reproduced by Google Cloud users.